This is based on a quote I've seen on a securitymetrics mailing list, that I belong to.
Somebody reported that "an average Windows box takes about $1K/year in security-related costs including all of the add-on software, maintenance, rebuilds, etc."
Upon hearing this the person asked the obvious question: "why they don't just buy a new one[computer] every 6 months and not bother... selling the used ones of course generates additional income as well."
And he never gets a [sensible] answer! Doesn't seeing stuff like this makes you lose all faith in the humankind? :-) Or at least in the IT part of it?
I've also heard that some folks buy new computers when the old ones becomes too slow from too much spyware (can't find the source right now). Good idea, considering the above? :-)